Diagnostic Testing for Recent Head Injury and Chronic Lower Back Pain
Order a non-contrast CT head immediately to evaluate the head injury from 2 days ago, given the mechanism (fall with direct head impact), presence of scalp hematoma, and ongoing headache. 1, 2
Head Injury Evaluation
Indications for CT Head
Your patient meets multiple criteria from validated clinical decision rules that mandate head CT imaging:
- Age >65 years is a high-risk factor per the Canadian CT Head Rule for neurosurgical intervention 2
- Dangerous mechanism of injury (fall with leg giving out, forward fall into wall) qualifies as moderate risk 2, 3
- Persistent headache 2 days post-injury with a scalp hematoma ("knot") warrants imaging 2
The American College of Radiology designates non-contrast head CT as "usually appropriate" and the gold standard for acute head trauma, as it rapidly detects neurosurgical emergencies including hemorrhage, herniation, and hydrocephalus with high sensitivity for acute hemorrhage. 4, 1, 2
Why CT is Necessary Despite Lack of Loss of Consciousness
Even in patients with minimal head injury (no loss of consciousness), the Canadian CT Head Rule was 100% sensitive for detecting intracranial hemorrhage when high or moderate risk factors were present. 3 Your patient has two risk factors (age >65 and mechanism), making imaging mandatory rather than optional.
Approximately 10% of patients with mild head trauma will have positive findings on head CT, and 1% will require neurosurgical intervention. 2 The 2-day delay since injury does not eliminate risk—delayed complications can occur, though they are rare (0.04% in one large study). 5
Common Pitfall to Avoid
Do not attribute the fall solely to the "leg giving out" without ruling out intracranial pathology first. The fall mechanism itself (forward into wall with head impact) combined with age >65 years mandates imaging regardless of the precipitating cause of the fall. 2
Lower Back Pain Evaluation
No Urgent Imaging Indicated
For the chronic lower back pain (15 years post-MVA with known bulging disc):
- No imaging is indicated at this visit unless there are new red flag symptoms not mentioned in your presentation [@general medical knowledge]
- Red flags that would change this recommendation include: new bowel/bladder dysfunction, saddle anesthesia, progressive motor weakness, fever, or history of cancer [@general medical knowledge]
The patient reports chronic pain rated 8/10 with no mention of new neurological deficits beyond the acute "leg giving out" episode that precipitated the fall. This single episode requires evaluation in the context of the head injury first.
Management Focus
The chronic back pain warrants conservative management optimization (physical therapy, medication adjustment, weight-bearing exercise program) rather than repeat imaging, given the 15-year chronicity and previously documented bulging disc. [@general medical knowledge]
Fatigue Evaluation
The patient mentions "no improvement in fatigue" despite taking medications as prescribed. Basic laboratory work may be reasonable (CBC, comprehensive metabolic panel, TSH) if not recently performed, but this is secondary to the acute head injury evaluation. [@general medical knowledge]
Imaging Protocol Summary
Order immediately:
Do not order at this visit:
- Lumbar spine imaging (chronic condition, no new red flags)
- MRI head (inappropriate for initial acute trauma evaluation—too slow and patient assessment takes priority) 1, 6
- Skull radiographs (cannot characterize intracranial pathology) 2
If CT head is negative but neurological status changes, consider repeat CT or MRI. 2 However, patients with normal CT and normal neurological examination have very low risk (0.006%) of deterioration. 2